Abstract
One of the most prominent climate tipping elements is the Atlantic meridional overturning circulation (AMOC), which can potentially collapse because of the input of fresh water in the North Atlantic. Although AMOC collapses have been induced in complex global climate models by strong freshwater forcing, the processes of an AMOC tipping event have so far not been investigated. Here, we show results of the first tipping event in the Community Earth System Model, including the large climate impacts of the collapse. Using these results, we develop a physics-based and observable early warning signal of AMOC tipping: the minimum of the AMOC-induced freshwater transport at the southern boundary of the Atlantic. Reanalysis products indicate that the present-day AMOC is on route to tipping. The early warning signal is a useful alternative to classical statistical ones, which, when applied to our simulated tipping event, turn out to be sensitive to the analyzed time interval before tipping.
I’m no climate scientist so I find this paper hard to interpret. Am I correct that they believe their early warning model indicates that the AMOC may be collapsing and if so, that Europe may face 3°C decreases per decade? And that that would essentially mean that large parts of europe would not be capable anymore to support populations of current size?
It’s very speculative, but compare some places in Canada of similar latitudes in regards to population density and possibility to grow food to those in Europe. Very few people realize how atypically mild the European climate is relative to how far north most of it is.
So… I’m also not a climate scientist, but I also research dynamical systems within a time-based series (computer scientist). All of the research on this is very difficult to read, but it all sort of leads up to the fact that we are approaching some sort of tipping point where the system, in this case climate, will bifurcate. Meaning things will be different and can turn into chaos (chaos theory).
I’ve spoken with Dr. Edward Ott at University of Maryland on his work with climate change, and I’ve spoke with chaos theory researchers at University of Arizona. It’s all very abstract, and it’s difficult to predict what this actually means for the climate and for us.
